1. Field of the Invention
The present invention relates to a detachable drawer rail, and more particularly to a detachable drawer rail having a retaining device.
2. Description of Related Art
Detachable drawer rails are normally used with drawers or keyboard racks of computer desks and are mounted on side faces of the drawers or similar features to mount the drawer or rack in a desk. Multiple conventional detachable drawer rails are usually composed of a ball bearing race slidably mounted between an intermediate track and an inner rail so that the drawers can be easily removed. Additionally, retaining devices are secured on the detachable drawer rails to keep the drawers limited within a sliding range and to retain the drawers in a certain position when the drawer is pulled out of a desk.
There are several types of conventional detachable drawer rail available at present. For example with reference to FIGS. 6, 7 and 8, a first conventional detachable drawer rail and with reference to FIGS. 9, 10, and 11, a second conventional detachable drawer rail, both comprise a track (60), a rail (70) slidably mounted in the track (60) and a resilient plate (90) attached to the rail (70). The first and second conventional detachable drawer rails further comprise a bearing race (80) mounted between the track (60) and the rail (70) to make the rail (70) slide more easily in the track (60).
Now referring to FIGS. 6-8 of the first conventional detachable drawer rail, the track (60) is adapted to be fixed to an inner face of a compartment of a furniture item and has a limit tab (64) secured on one end of the track (60) to avoid the bearing race (80) falling from the track (60). The track (60) further has a limit block (66) with two locking protrusions (662) secured on the other end of the track (60) to prevent the rail (70) completely sliding out of the furniture item.
The rail (70) is adapted to be secured to a side-wall of a drawer and has an opening (72) defined in a middle portion of the rail (70). An attachment hook (74) and a locking block (76) are formed on one side and the other side of the rail (70) near the opening (72) respectively. A recess (762) is defined in the rail (70) near a base of the locking block (76).
The resilient plate (90) is flexible and has a front fork (92) formed at one end of the resilient plate (90) to be jammed with the attachment hook (74) of the rail (70). The resilient plate (90) has a round bottom nose (94) embossed under a bottom side of the resilient plate (90) to wedge into the recess (762) of the rail (70). Therefore, the resilient plate (90) is detachably secured on the rail (70).
Now referring to FIG. 8, when the drawer is pulled outwardly, the locking protrusion (662) blocks the resilient plate (90) at one vertical retaining flat (666) so as to efficiently prevent the drawer from being completely pulled out of the compartment of the furniture item. When the drawer is released, the resilient plate (90) is pressed toward to the rail (70) to make the resilient plate (90) have no contact with the retaining flat (666) and then the engagement of the rail (70) and the track (60) is released.
However, when users press the resilient plate (90), fingers often are stained with lubrication coated on elements of the retaining device. Additionally, the round bottom nose (94) of the resilient plate (90) is easily rocked inside the recess (72) so as to make the whole retaining device unstable in use.
As to the second conventional detachable drawer rail as shown in FIGS. 9-11, the track (60) is adapted to be fixed to an inner face of a compartment of a furniture item and has a limit tab (64) secured on one end of the track (60) to avoid the bearing race (80) falling from the track (60). The track (60) further has a limit block (66) with two locking protrusions (662) secured on the other end of the track (60) to prevent the rail (70) completely sliding out of the compartment of the furniture item.
The rail (70) is adapted to be secured to the side-wall of the drawer and has an opening (72) defined in a middle portion of the rail (70). A lip (71) is formed on the rail (70) near the opening (72) and a hole (73) is defined in the rail near the opening (72) at an opposite side to the lip (71).
The resilient plate (90) is flexible and has a tab (91) formed at one end of the resilient plate (90) to be jammed with the lip (74) of the rail (70). The resilient plate (90) further has a through hole (93) defined in the other end of the resilient plate (90). The through hole (93) corresponds to the hole (73) of the rail (70) and a pin (931) penetrates the through hole (93) and the hole (73) so as to make the resilient plate (90) detachably and firmly secured on the rail (70). Additionally, two ports (95) are defined respectively in opposite edges of a middle portion of the resilient plate (90).
Now referring to FIGS. 10 and 11, when the drawer is being pulled outwardly, the resilient plate (90) is pressed downwardly by resisting the locking protrusions (662) of the limit block (66). Then, the drawer is stopped when the locking protrusions (622) are retained inside the port (95) of the resilient plate (90) as shown in FIG. 11. A pushing end (961) urging against the locking protrusions (622) comprises a guiding arc (963) so that when the drawer is pushed hard a little, the guiding arc (963) makes the locking protrusion (662) released from the port (95). Then, the drawer is able to retract in the compartment of the furniture item.
Therefore, the shape of the guiding arc (963) is important, and especially in its precise angle. When the angle is overly curved, the limit block (66) loses its positioning function and the drawer is excessively movable. On the contrary, when the angle is not curved enough, the drawer is not easily pushed back to the compartment by the users. Besides, a pushing force to overcome the resilient plate (90) by the guiding arc (963) works axially so that the resilient plate (90) itself is easily broken in the middle portion and other places, especially the tab (92).
To overcome the shortcomings of these two conventional detachable drawer rails, the present invention provides a detachable drawer rail to mitigate and obviate the aforementioned problems.
A first objective of the invention is to provide a detachable drawer rail that is easy to operate and has excellent positioning efficiency.
A second objective of the invention is to provide a detachable drawer rail that is firm and steady when being used.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.